TECHNICAL FIELD
[0001] The present invention relates to a chassis of a vehicle.
[0002] The present invention is advantageously applied to the chassis of an automobile,
to which explicit reference will be made in the following description without therefore
loosing in generality.
PRIOR ART
[0003] A chassis of an automobile normally consists of a central body, forming the passenger
compartment, and a front body supporting the front wheels and a rear body supporting
the rear wheels. The engine may be arranged in frontal position, and thus accommodated
in the front body, or in central or rear position, and thus accommodated in the rear
body.
[0004] At the passenger compartment and approximately in the middle of the automobile, the
chassis comprises two central pillars, each of which rises vertically from a door
sill and ends at the roof. In most automobiles on the market, each side (comprising
the door sill and the central pillar) is made of several pressed parts, which are
superimposed and welded. Such a constructive method is fast and cost-effective when
the material used for the chassis is steel and/or when a high number of parts are
made (i.e. for mass manufactured automobiles), while it is more complex and costly
when the material used for the chassis is aluminum and/or when a low number of parts
are made (i.e. for small series automobiles).
[0005] Patent application
EP1498345A2 describes a vehicle provided with a pair of door sills arranged longitudinally underneath
the zone of the doors, and each having a through hole; and a pair of central pillars,
each of which raises perpendicularly and vertically from a door sill, is made in one
piece, is inserted in an interlocking way in the through hole of a window sill, and
is welded to the window sill at the through hole.
DESCRIPTION OF THE INVENTION
[0006] It is the object of the present invention to provide a chassis for a vehicle, which
is free from drawbacks described above, and which is thus easy and cost-effective
to make when the material used for the chassis is aluminum and/or when a low number
of parts are made (i.e. for small series vehicles).
[0007] According to the present invention, a chassis of a vehicle is provided as disclosed
in the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] The present invention will now be described with reference to the accompanying drawings,
which illustrate a non-limitative embodiment thereof, in which:
- figure 1 is a diagrammatic, perspective view of a chassis of a vehicle made in accordance
with the present invention;
- figure 2 is a perspective view of a door sill and a central pillar of the chassis
in figure 1;
- figure 3 is a perspective, exploded view of the door sill and of the central pillar
in figure 2; and
- figure 4 is a perspective bottom view of the door sill and of the central pillar in
figure 2.
PREFERRED EMBODIMENTS OF THE INVENTION
[0009] In figure 1, numeral 1 indicates as a whole a chassis of an automobile comprising
a central body 2, in which a passenger compartment is defined, a front body 3, in
which a front boot is defined, and rear body 4, in which an engine compartment is
defined. The front body 3 and the rear body 4 are preferably bolted to the central
body 2 so as to be disassembled if needed. Furthermore, the chassis 1 comprises a
floor pan (not shown), which is inferiorly bolted at least to the central body 2.
[0010] The central body 2 of the chassis 1 is made of aluminum by welding several components,
and in particular the central body 2 comprises a plurality of linear bars, which display
a constant section, are made by extrusion, and are joined together by welding at structural
nodes defined by junction bodies. Each junction body has a number of respective pockets
(not shown in detail), which are adapted to elongate the head of corresponding linear
bars. In particular, four junction bodies are present (two front junction bodies and
two rear junction bodies) at the attachment zone of each suspension.
[0011] Two linear bars of the central body 2 arranged longitudinally underneath the door
zone form the door sills 5 (i.e. the lower part underneath the doors which extends
from the end of the front wheel arch to the beginning of the rear wheel arch). A central
pillar 6 rises perpendicularly and vertically from each door sill 5, which extends
from the door sill 5 to an upper bar which is arranged longitudinally and defines
a side end of the roof.
[0012] As shown in figure 2-4, each central pillar 6 consists of a one-piece or monolithic
extrusion (i.e. free from parts added by welding, screwing, riveting or other mechanical
connection methods). Each door sill 5 has a through hole 7, in which a central pillar
6 is inserted in an interlocking way; furthermore, each central pillar 6 is welded
to the door sill 5 at the through hole 7.
[0013] Each central pillar 6 comprises an internal tubular body 8 inserted coaxially inside
an external tubular body 9; both bodies 8 and 9 have a rectangular transversal section
and are connected to one another by means of two flat plates 10, which connect the
internal tubular body 8 to the external tubular body 9 and are arranged reciprocally
coplanar on opposite sides of the internal tubular body 8.
[0014] Preferably, the internal tubular body 8 of each central pillar 6 extends along the
extension of the central pillar 6 itself, while the external tubular body 9 of each
central pillar 6 extends only along a lower portion of the central pillar 6 itself
arranged at the door sill 5 (in particular, the external tubular body 9 of each central
pillar 6 extends inside the door sill 5 and partially even outside the door sill 5).
This shape of each central pillar 6 allows to obtain high mechanical strength at door
sill 5 (i.e. when the main mechanical stress occurs) combined with a low total weight.
[0015] In order to minimize the weight of each central pillar 6, the two flat plates 10
of each central pillar 6 have windows 11 (i.e. reliefs made by eliminating material)
arranged outside the external tubular body 9.
[0016] Underneath, each central pillar 6 is inserted in an interlocking way inside a hole
7 of a door sill 5 and is also welded to the door sill 5; superiorly, each central
pillar 6 is fixed to an upper part of the chassis 1. The fastening of each central
pillar 6 to the upper bar may be similar to the fastening of the central pillar 6
to the door sill 5 (thus the upper bar has a through hole which accommodates the central
pillar 6, which is also welded to the upper bar itself), or the central pillar 6 may
also be welded to the upper bar.
[0017] According to a preferred embodiment, each door sill 5 is initially made in one piece
by extrusion and then mechanically machined by elimination of material to remove the
unnecessary parts (i.e. by mechanically cutting part of the external tubular body
9 and mechanically cutting the plates 10 to make the windows 11).
[0018] The above-described chassis 1 has many advantages.
[0019] Firstly, the above-described chassis 1 is very robust with respect to side collisions
because it has very high mechanical strength in the connection between the door sill
5 and a central pillar 6; in particular, such as result is obtained by mechanically
inserting the central pillar 6 in the through hole 7 of the door sill 5 in an interlocking
way.
[0020] Furthermore, the above-described chassis 1 is simple and cost-effective to make,
also when the material used for the chassis is aluminum.
[0021] Finally, the above-described chassis 1 is simple and cost-effective to make, also
when a low number of parts is made (i.e. for small series automobiles).
1. Chassis (1) of a vehicle; the chassis (1) comprises:
a pair of door sills (5) arranged longitudinally below the area of the doors and each
of which presents a through hole (7); and
a pair of central pillars (6), each of which is realized in one single piece by extrusion,
rises perpendicularly and vertically from a door sill (5), is inserted in an interlocking
way inside the through hole (7) of the door sill (5), and is welded to the door sill
(5) in correspondence of the through hole (7);
the chassis (1) is characterized in that each central pillar (6) comprises an internal tubular body (8) which is inserted
coaxially inside an external tubular body (9); and at least two flat plates (10) which
connect the internal tubular body (8) to the external tubular body (9) and are arranged
coplanar to each other on opposite sided of the internal tubular body (8).
2. Chassis (1) according to claim 1, wherein the tubular bodies of each central pillar
(6) present a rectangular transversal section.
3. Chassis (1) according to claim 1 or 2, wherein the internal tubular body (8) of each
central pillar (6) extends along the whole length of the central pillar (6).
4. Chassis (1) according to claim 1, 2 or 3, wherein the external tubular body (9) extends
only along a lower portion of the central pillar (6) itself arranged in correspondence
of the door sill (5).
5. Chassis (1) according to claim 4, wherein the external tubular body (9) of each central
pillar (6) extends even outside the door sill (5).
6. Chassis (1) according to claim 4 or 5, wherein the two flat plates (10) present windows
(11) arranged outside the external tubular body (9).
7. Chassis (1) according to one of the claims from 1 to 6, wherein each door sill (5)
is initially realized in one single piece by extrusion and, subsequently, it is mechanically
processed in order to eliminate those parts which are not necessary.